Multi-leverage fluid pressure pump



June 1959 7 CJR. MARCUM 2,891,480

MULTI-LEVE'RAGE FLUID PRESSURE PUMP Filed Oct. 4, 1957 2 Sheet-Sheet 1 v FIRST LEVER) ll" E II sscouoff 'i LEVER- 42 socK:-:T|a

I v a 2 20- A? I l6 3 3; l mLevls l6 (PISTON 2 E] I cYuNoEr+ a VINVENTOR. CHARLES R. MARCUM ATTORNEY June 23, 1959 c. R. MARCUM MULTI-LEVERAGE FLUID PRESSURE PUMP 2 Sheets-Sheet 2 Filed dct. 4, 1957 SHAPED LATCH MEMBER 34 SECOND LEVER X HANDLE l9 FIRST LEVER SECOND AXIS 7 LOW Posmorv SECOND LEVER LOW POSITION INVENTOR. FI LEVER CHARLES R.MARCUM ATTORNEY MULTI-LEVERAGE FLUID PRESSURE PUMP Charles R. Marcum, Jelfersontown, Ky., assignor to Gemco Development and Engineering Company, Louisville, Ky., a corporation of Kentucky Application October 4, 1957, Serial No. 688,224 15 Claims. (Cl. 103-38) This invention relates to handle-operated fluid pressure pumps of the multi-leverage ratio type. Such pumps provide two or more different ranges of pressure through two or more different leverage ratios.

A conventional handle-operated pump includes: a pump cylinder on a frame; a slidable piston in the cylinder; and a piston-operating handle pivoted at spaced points to the frame and the piston. The leverage ratio of this pump can be and conventionally is changed by adjusting the spacing between these two pivotal connections. Usually this is done by shifting one of them, such as the fulcrum for the handle, from one position on the frame to another.

The principal object of the present invention is to improve this type of pump and, more particularly, to provide it with a novel arrangement of fulcrums which permit a rapid shift from one leverage ratio to another and which provides, in each case, a rigidly mounted fulcrum and a stable fulcrum connection.

Another important object is to provide a simple, sturdy, inexpensive and quickly operated arrangement for shifting from one leverage ratio to another.

The objects of the present invention are largely achieved simply by pivotally connecting a first lever to the frame for oscillation about a first axis and a second lever to the first lever for oscillation about a second axis, by connecting the second lever to the piston and by latching or unlatching the two levers. With this arrangement, when the two levers are latched together, the first provides one operating leverage ratio whereas, when they are unlatched, the second provides a different operating leverage ratio. While two different leverage ratios are thus provided, a fixed fulcrum and a stable fulcrum connection is employed in each case, the first fulcrum being fixed to the frame and the second fulcrum to the first lever.

The invention is illustrated in the accompanying drawings wherein: a

Fig. 1 is a partly cut-away perspective view of the pump with the pump operating handle withdrawn a short distance from its socket;

Fig. 2 is a front elevational view of the pump with the handle omitted;

a Fig. 3-

a side elevational view of the pump with its levers latched together, the frame of the near side of the pump being omitted for the sake of. clarity;

, Fig. 4 is a. fragmentary side-elevational view of the pump with its levers unlatched;

Fig. Sis a perspective view of the second lever of the p p; r r

Fig. 6 is a partly cut-away fragmentary perspective view similar to Fig. 1 of another embodiment of the pump;

. Fig. 7 is. a perspective view of the second lever of the modified pump;

Fig. 8 is a perspectiveview of the latching member of the modified pump; and

Fig. 9 is a fragmentary central section of the modified pump showing the pump handle in the uppermost position it oceupiesfor both long strokes about the first axis and short strokesabout the second axis, its lowermost position atent 2,891,480 Patented June 23, 1959 EMBODIMENT OF FIGS. l-5

The pump 1 comprises a frame 2 having a pair of horizontally spaced vertical sideplates 3 which are interconnected at their upper ends by a cross bar 4 and at their lower ends by a vertically arranged pump cylinder 5. The sideplates 3 are joined to the cross bar 4 and the cylinder 5 by conventional means such as by welding or by threaded fasteners. The pump cylinder 5 slidably houses a vertically reciprocating piston 6 which extends from the upper end or mouth of the cylinder 5. The cylinder 5 further includes: a single port 7 for interconnecting the cylinder through one check valve with a fluid supply system and through a reversely operating check valve with a fluid pressure system; a packing 8 at its upper end en circling the piston 6 to seal the space between the cylinder and the piston; and a cooperating packing nut 9 threaded into the mouth of the cylinder to provide a tight seal around the piston 6. The foregoing structure is conventional and forms no part of my invention except insofar as it cooperates with my novel pump operating structure which is to be described.

The cooperating means for the pump 1 includes: a first lever pivoted to the frame 2 for oscillation about a first axis; a second lever pivoted to the first lever for oscillation about a second axis; means connecting the piston 6 to the second lever to render it operable to reciprocate the piston when the second lever is oscillated about said second axis; and means for securing the first and second levers together to render the first lever operable to reciprocate said platen when oscillated about said first ax1s.

The first lever is in the form of a clevis 10 having an axial web 10, axial trunnions 11 at opposite ends of the web and spaced side arms 12 extending radially from opposite end portions of the web. The axis of the trunnions 11 constitute the first axis. The clevis 10 is positioned between side plates 3 of the frame and pivotally mounted thereon by the trunnions 11 which are journalled in suitable bearing holes therein; The upward pivotal movement of the clevis it), about the first axis, is limited by a cross bar 4 which abuts the upper edges of the side arms 12 of the clevis when the'clevis is swung to its uppermost position.

The second lever is in the form of a relatively thick gate 13 having a heavy body portion. This gate is positioned between the spaced side arms 12 of the clevis 10. It is pivotally mounted on the first lever for oscillation about the second axis by journals 14, which are located at one end of the gate 13 and which project from opposite sides thereof into suitable bearing holes in the clevis side arms12.

The means interconnecting the piston and the second lever include: a pair of crank pins 15, one eccentrically mounted on the outer end of each journal 14; and a clevis 16 extending from the crank pins 15 to the piston 6 and pivotally connected to both. The crank pins 15 are axially aligned with each other. Each pin is mounted to project axially from its journal 14 beyond the outer side of the adjacent clevis side arm 12. The clevis 16 includes: a web 16 extending horizontally from one side of the projecting portion of the piston 6 to the other and pivotally connected thereto at its center; and a pair of spaced clevis arms 17 extending from opposite ends of the web 16', upwardly to and pivotally connected with the opposite eccentric crank pins 15.

With this arrangement, it will be appreciated that when the second lever or gate 13 is oscillated about the second axis, the crank pins 15 will be similarly oscillated about that axis and thus effective through clevis 16 to recipro cate the piston. In order to oscillate the second lever, the free end of the gate 13 is centrally provided with a radially extending socket 18 designed to receive a pump operating handle 19.

The first and second levers are secured together in a manner permitting ready connection and disconnection by means of a slot-and-pin connection provided therebetween. Thus the outer ends of the second lever gate 13 and of the first lever side arms 12 are similarly slotted to provide a transverse recess for receiving a cross pin on the handle. The second lever is slotted at 21 and the first lever at 22 while the handle is provided with cross pin 23. When these parts are aligned radially and the adjacent end of the handle is thrust into the handle receiving socket 18 of the second lever sufiiciently to move cross pin 23 into the transverse recess formed by aligned slots 21 and 22, the cross pin 23 will thus function mechanically to latch the second lever to the first lever. This prevents the second lever from being oscillated about the second axis and renders the first lever operable to reciprocate the piston when oscillated about the first axis.

If desired, the second lever may be provided with aligned recesses 20 extending at right angles to its recesses 21 in position to receive cross pin 23 when it is turned 90 out of its lever latching position.

OPERATION When the handle 19 is inserted within the socket 18 with its cross pin 23 extending horizontally and seated in the horizontally aligned slots 21 and 22, the gate member 13 of the second lever is latched to the first lever clevis 10. A pumping movement of the handle 19 will now oscillate the first lever about the first axis. When a higher mechanical advantage or leverage ratio is desired, the handle 19 is moved outwardly sufiiciently to remove pin 23 from slots 21 and 22 and then operated. Preferably it is rotated 90 and moved inwardly to seat the cross pin 23 in slots 20 before instituting the pumping operation. A pumping movement of the handle 19 will now oscillate the second lever about the second axis. At the very beginning of this operation, the first lever will assume and remain in a raised position abutting the cross bar 4.

With this design, wide differences in the mechanical advantage or leverage ratios may be simply and quickly obtained between levers 1 and 2 depending primarily upon the distance provided between the two oscillating axes and axis C. One arrangement providing a change in the mechanical advantage or leverage ratio ranging from 10.0 to 50.0, for example, is indicated in Table I which follows:

EMBODIMENTS OF FIGS. 6-8

This pump is substantially the same as the first embodiment except that: (a) the first lever 10 is provided with an outer cross bar connecting the outer ends of its side arms 11; (b) the second lever 31 is in the form of a thick shaft 31, the central portion of which is ground on its top and bottom to provide it with a pair of parallel diametrically opposite flats 26; (c) an H-shaped latch member is mounted therebetween for slidable movement between outer latching and inner unlatching positions; and (d) the handle 19 is connected to the latch member.

It will be understood that the first lever 10 is in the form of a clevis 10 having an axial web 10', axial trunnions 11 and spaced radial side arms 12, the outer ends of the latter being interconnected by a cross bar 30. As before, it oscillates about a first axis, which coincides with that of web 10 and trunnion 11.

While the second lever is now in the form of a shaft 31 having diametrically opposite flats 32, its end portions function as journals 14 and are provided with eccentric pins 15 for interconnection with the piston through the arms 17 of a clevis. As before, it oscillates about a second axis, which coincides with that of journals 14.

The H-shaped latch member 34 has relatively shallow and deep recesses 35 and 36 formed between the legs of the H on the outer and inner sides respectively of its cross bar. This latch member 34 transversely bridges the space between side arms 12 and slidably moves radially therealong between its outer latching and inner unlatching position. In its outer latching position, its shallow outer recess 35 cooperates with cross bar 30 to provide a slot-and-pin connection between the latch member 34 and the first lever 10 while its deep inner recess 36 cooperates with the flattened portion 32 of the second lever to provide a slot-and-pin connection therebetween. In its inner unlatching position, the outer slot-and-pin connection with the first lever is broken while the inner slot-and-pin connection with the second lever remains.

The handle 19 may be permanently connected to the latch member 34 but preferably is inserted in a suitable socket therein from which it may be readily removed when desired.

The operation, of course, is as before. The latch member is moved by the handle 19 to and held in its outer latching position when a low ratio, long stroke is desired and in its inner unlatching position when a high ratio, short stroke is desired.

Having described my invention, I claim:

1. A multi-leverage pump comprising: a frame carrying a pump cylinder having a slidably mounted piston; a first lever pivoted to said frame for oscillation about a first axis; a second lever pivoted to said first lever for oscillation about a second axis; means connecting the piston to the second lever to render it operable to reciprocate the piston when the second lever is oscillated about said second axis; and means for latching the first and second levers together to render the first lever operable to reciprocate said piston when oscillated about said first axis.

2. The pump of claim 1 wherein: said first and second levers provide relatively small and large pump-operating leverage ratios respectively.

3. The pump of claim 2 wherein: the second lever is mounted on the first lever through a journal which is oscillatable about the second axis.

4. The pump of claim 3 wherein: said journal has an eccentric pin through which the second lever is connected to the piston.

5. The pump of claim 2 wherein: said latch means includes an elongate handle connected to said second lever for movement longitudinally between one position, in which both levers are latched together, and another position, in which the first lever is unlatched from the second lever.

6. The pump of claim 5 wherein: the latch means includes a make and break pin-and-slot connection between the handle and the first lever.

7. The pump of claim 2 including: stop means mounted on the frame to limit the movement of the first lever in the piston withdrawing direction.

8. The pump of claim 2 wherein: the first lever includes a clevis having a web pivotally mounted on the frame for oscillation about the first axis and a pair of arms extending outwardly from the Web.

9. The pump of claim 8 wherein: the second lever is in the form of a gate positioned between the clevis arms of a the first lever and pivotally mounted thereon for oscillation about the second axis.

10. The pump of claim 9 wherein: the piston is connected to the gate through a pair of eccentric pins which are mounted on the gate for movement with the gate.

11. The pump of claim 10 wherein: both levers include a common elongate handle which is longitudinally movable between inner and outer positions and operable, in one position, to latch the clevis arms of the first lever and the gate of the second lever together, and, in the other position, to remain connected to the second lever and be disconnected from the first lever.

12. The pump of claim 2 wherein: said latch means includes a latch member adapted to be slidably mounted on the second lever for movement from one position, wherein it is connected to both levers, to another position, wherein it remains connected to the second lever but is disconnected from the first lever.

13. The pump of claim 12 wherein: the latch member is slidably movable along a predetermined path between inner and outer positions and cooperates with the second lever to provide a pin-and-slot connection therebetween in both positions and also cooperates with the first lever to provide a pin-and-slot connection only in one of said positions.

14. The pump of claim 13 wherein the latch member includes an operating pump handle secured to the latch member.

15. A multi-leverage pump comprising: a frame carrying a pump cylinder having a slidably mounted piston; a first lever pivoted to said frame for oscillation about a first axis; a second lever pivoted to said first lever for oscillation about a second axis; and means connecting the piston to the second lever to render the second lever operable to reciprocate the piston when the second lever is oscillated about said second axis and to render the first lever operable to reciprocate the piston when the first lever is oscillated about said first axis.

References Cited in the file of this patent UNITED STATES PATENTS 476,082 Sellon May 31, 1892 599,073 Burke Feb. 15, 1898 1,516,500 Richards Nov. 25, 1924 

